The simple answer is that in a wet year the grasses will grow taller and burn well. In dry years, they’re not as tall, burn just as well but sooner in the season too. It basically doesn’t matter for light fuels like grass.
Fuels are broken down into hourly ratings of fuel moisture. Grasses are one hour fuels, they’ll (when dead) follow the humidity by one hour. Thicker fuels take longer (10, 100, 1000 and 10k hour), live fuel moisture (can be more than 100%, based on cellular weight of the plant, water:cells) longer again. In dry years, the 10-1000 hour fuel moisture becomes more important than in ‘wet’ years but not by much. Fuels will burn in any year, they always dry out starting when the rain stops, so the length of the fire season is the variable.
Ignition is the problem. Almost all wildland fires are human caused (lightning being the exception; critters don’t leave glass litter, smoke or leave campfires or drive in tall grass…). Yes, this is way over simplified, please don’t pick nits.
Rick
From: debbygirl55
If we continue the "dry" spell until summer will our fire danger be more dangerous even though we have received the over-amounts of rainfall? I know it seems a silly question but the ground is pretty saturated here in Nor-cal.
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